Repairing roads by applying an overlay, such as an asphalt overlay, to the road surface is well known in the art. A serious drawback of this method includes reflective cracking. Reflective cracking is the process by which an existing crack, discontinuity or joint propagates towards the surface through an overlying layer of asphalt.
Once a reflective crack reaches the surface, an open path is created allowing the penetration of water into the lower layers of the pavement. Left untreated, this situation will lead to further deterioration of the pavement structure and to a reduction in overall serviceability.
The use of interlayers, such as steel wire meshes, geogrids, non-woven structure and stress relieve membranes also called stress absorbing interlayers or SAMI has gained widespread acceptance. Products of varying types have been used to either reinforce the asphalt or to provide a relatively impermeable layer within it, thereby improving the long-term performance of the pavement.
Although it has been proven that steel meshes such as hexagonal woven meshes, are successful to reduce cracking in the overlay, steel meshes have the drawback that the installation is difficult due to the rigid nature of such steel meshes.
A further drawback of the use of steel meshes is that thick overlay layers of for example 8 cm or more are required in order to be efficient.
Geogrids are commonly made of a polymer material (for example polyester, polyethylene or polypropylene), made of glass (for example glass rovings) or made of carbon (for example carbon filaments). Polymer material and glass material have a limited strength. Furthermore, polymer material can lose its integrity due to the high temperature of the asphalt during installation (160° C.). Glass can get damaged during its installation due to its brittle nature and requires additional protection.